This is similar to TCP MD5 in functionality but it's sufficiently different that wire formats are incompatible. Compared to TCP-MD5 more algorithms are supported and multiple keys can be used on the same connection but there is still no negotiation mechanism. Expected use-case is protecting long-duration BGP/LDP connections between routers using pre-shared keys.
This version is mostly functional, it incorporates ABI feedback from previous versions and adds tests to kselftests. More discussion and testing is required and obvious optimizations were skipped in favor of adding functionality. Here are several flaws:
* RST and TIMEWAIT are mostly unhandled * Locking is lockdep-clean but need to be revised * Sequence Number Extension not implemented * User is responsible for ensuring keys do not overlap * Traffic key is not cached (reducing performance)
Not all ABI suggestions were incorporated, they can be discussed further. However I very much want to avoid supporting algorithms beyond RFC5926.
Test suite was added to tools/selftests/tcp_authopt. Tests are written in python using pytest and scapy and check the API in some detail and validate packet captures. Python code is already in linux and in kselftests but virtualenvs not very much. This test suite uses `tox` to create a private virtualenv and hide dependencies. Let me know if this is OK or how it can be improved.
Limited testing support is also included in nettest and fcnal-test.sh, those tests are slow and cover much less.
Changes for frr: https://github.com/FRRouting/frr/pull/9442 That PR was made early for ABI feedback, it has many issues.
Changes for yabgp: https://github.com/cdleonard/yabgp/commits/tcp_authopt The patched version of yabgp can establish a BGP session protected by TCP Authentication Option with a Cisco IOS-XR router. It old now.
Changes since RFCv2: * Removed local_id from ABI and match on send_id/recv_id/addr * Add all relevant out-of-tree tests to tools/testing/selftests * Return an error instead of ignoring unknown flags, hopefully this makes it easier to extend. * Check sk_family before __tcp_authopt_info_get_or_create in tcp_set_authopt_key * Use sock_owned_by_me instead of WARN_ON(!lockdep_sock_is_held(sk)) * Fix some intermediate build failures reported by kbuild robot * Improve documentation Link: https://lore.kernel.org/netdev/cover.1628544649.git.cdleonard@gmail.com/
Changes since RFC: * Split into per-topic commits for ease of review. The intermediate commits compile with a few "unused function" warnings and don't do anything useful by themselves. * Add ABI documention including kernel-doc on uapi * Fix lockdep warnings from crypto by creating pools with one shash for each cpu * Accept short options to setsockopt by padding with zeros; this approach allows increasing the size of the structs in the future. * Support for aes-128-cmac-96 * Support for binding addresses to keys in a way similar to old tcp_md5 * Add support for retrieving received keyid/rnextkeyid and controling the keyid/rnextkeyid being sent. Link: https://lore.kernel.org/netdev/01383a8751e97ef826ef2adf93bfde3a08195a43.1626...
Leonard Crestez (15): tcp: authopt: Initial support and key management docs: Add user documentation for tcp_authopt selftests: Initial tcp_authopt test module selftests: tcp_authopt: Initial sockopt manipulation tcp: authopt: Add crypto initialization tcp: authopt: Compute packet signatures tcp: authopt: Hook into tcp core tcp: authopt: Add snmp counters selftests: tcp_authopt: Test key address binding selftests: tcp_authopt: Capture and verify packets selftests: Initial tcp_authopt support for nettest selftests: Initial tcp_authopt support for fcnal-test selftests: Add -t tcp_authopt option for fcnal-test.sh tcp: authopt: Add key selection controls selftests: tcp_authopt: Add tests for rollover
Documentation/networking/index.rst | 1 + Documentation/networking/tcp_authopt.rst | 69 + include/linux/tcp.h | 6 + include/net/tcp.h | 1 + include/net/tcp_authopt.h | 134 ++ include/uapi/linux/snmp.h | 1 + include/uapi/linux/tcp.h | 110 ++ net/ipv4/Kconfig | 14 + net/ipv4/Makefile | 1 + net/ipv4/proc.c | 1 + net/ipv4/tcp.c | 27 + net/ipv4/tcp_authopt.c | 1168 +++++++++++++++++ net/ipv4/tcp_input.c | 17 + net/ipv4/tcp_ipv4.c | 5 + net/ipv4/tcp_minisocks.c | 2 + net/ipv4/tcp_output.c | 74 +- net/ipv6/tcp_ipv6.c | 4 + tools/testing/selftests/net/fcnal-test.sh | 34 + tools/testing/selftests/net/nettest.c | 34 +- tools/testing/selftests/tcp_authopt/Makefile | 5 + .../testing/selftests/tcp_authopt/README.rst | 15 + tools/testing/selftests/tcp_authopt/config | 6 + tools/testing/selftests/tcp_authopt/run.sh | 11 + tools/testing/selftests/tcp_authopt/setup.cfg | 17 + tools/testing/selftests/tcp_authopt/setup.py | 5 + .../tcp_authopt/tcp_authopt_test/__init__.py | 0 .../tcp_authopt/tcp_authopt_test/conftest.py | 21 + .../full_tcp_sniff_session.py | 53 + .../tcp_authopt_test/linux_tcp_authopt.py | 198 +++ .../tcp_authopt_test/netns_fixture.py | 63 + .../tcp_authopt/tcp_authopt_test/server.py | 82 ++ .../tcp_authopt/tcp_authopt_test/sockaddr.py | 101 ++ .../tcp_authopt_test/tcp_authopt_alg.py | 276 ++++ .../tcp_authopt/tcp_authopt_test/test_bind.py | 143 ++ .../tcp_authopt_test/test_rollover.py | 181 +++ .../tcp_authopt_test/test_sockopt.py | 74 ++ .../tcp_authopt_test/test_vectors.py | 359 +++++ .../tcp_authopt_test/test_verify_capture.py | 123 ++ .../tcp_authopt/tcp_authopt_test/utils.py | 154 +++ .../tcp_authopt/tcp_authopt_test/validator.py | 158 +++ 40 files changed, 3746 insertions(+), 2 deletions(-) create mode 100644 Documentation/networking/tcp_authopt.rst create mode 100644 include/net/tcp_authopt.h create mode 100644 net/ipv4/tcp_authopt.c create mode 100644 tools/testing/selftests/tcp_authopt/Makefile create mode 100644 tools/testing/selftests/tcp_authopt/README.rst create mode 100644 tools/testing/selftests/tcp_authopt/config create mode 100755 tools/testing/selftests/tcp_authopt/run.sh create mode 100644 tools/testing/selftests/tcp_authopt/setup.cfg create mode 100644 tools/testing/selftests/tcp_authopt/setup.py create mode 100644 tools/testing/selftests/tcp_authopt/tcp_authopt_test/__init__.py create mode 100644 tools/testing/selftests/tcp_authopt/tcp_authopt_test/conftest.py create mode 100644 tools/testing/selftests/tcp_authopt/tcp_authopt_test/full_tcp_sniff_session.py create mode 100644 tools/testing/selftests/tcp_authopt/tcp_authopt_test/linux_tcp_authopt.py create mode 100644 tools/testing/selftests/tcp_authopt/tcp_authopt_test/netns_fixture.py create mode 100644 tools/testing/selftests/tcp_authopt/tcp_authopt_test/server.py create mode 100644 tools/testing/selftests/tcp_authopt/tcp_authopt_test/sockaddr.py create mode 100644 tools/testing/selftests/tcp_authopt/tcp_authopt_test/tcp_authopt_alg.py create mode 100644 tools/testing/selftests/tcp_authopt/tcp_authopt_test/test_bind.py create mode 100644 tools/testing/selftests/tcp_authopt/tcp_authopt_test/test_rollover.py create mode 100644 tools/testing/selftests/tcp_authopt/tcp_authopt_test/test_sockopt.py create mode 100644 tools/testing/selftests/tcp_authopt/tcp_authopt_test/test_vectors.py create mode 100644 tools/testing/selftests/tcp_authopt/tcp_authopt_test/test_verify_capture.py create mode 100644 tools/testing/selftests/tcp_authopt/tcp_authopt_test/utils.py create mode 100644 tools/testing/selftests/tcp_authopt/tcp_authopt_test/validator.py
base-commit: 3a62c333497b164868fdcd241842a1dd4e331825